In the wild world of KZN, disruptive floods are now a seasonal reality — this is what we need to do

A road tanker washed up on a Durban beach amid floods and heavy rain on 12 April 2022 in Durban, South Africa. (Photo: Gallo Images / Darren Stewart)

By Derek Alberts

23 Mar 2025

Is higher rainfall and more floods the new normal in KwaZulu-Natal? While near-record rains in parts of the province may be ascribed to seasonal weather fluctuations, science holds a more austere view – that 12 disruptive floods over the past nine years represents a trend that is intensifying as the forces of climate change gather pace.

Heavy rains in the catchment of KwaZulu-Natal’s east-flowing rivers continue to cause extensive flooding in the greater Durban area, mostly to the detriment of vulnerable households unprepared for the disaster.

The bad news is that disruptive flooding is now a seasonal reality, and that communities need to be supported to build resilience to deal with these events. So says climate change expert Professor Tafadzwa Mabhaudhi, a climate change, food systems and health professor at the London School of Hygiene and Tropical Medicine and director of the Institute for Natural Resources with first-hand experience of the recent KZN floods.

“The March 2025 floods are the 12th in a series of events dating from July 2016,” he says. “Climate change is here to stay, and we need to adapt urgently.”

Mabhaudhi acknowledges that not all flooding events can be blamed on climate change due to a dearth of attribution studies.

“We know, however, that a warmer climate means more energy and moisture in the atmosphere, which means heavier rainfall in certain areas.”

KZN flooding The eThekwini Municipality says the devastating 2022 floods in KwaZulu-Natal led to increased water demand. De Bos Dam in the Hemel-en-Aarde valley was commissioned to provide the growing town of Hermanus with water. Completed in 1976, an annual extraction limit of 2.8 million cubic metres from the dam was established by a 1973 ruling of the Water Court. That limit has been repeatedly exceeded. (Photo: Sean Christie)

Of concern to Mabhaudhi are the below-the-radar consequences that linger long after the event.

“The dramatic sight of collapsed infrastructure and demolished buildings dominate attention at the expense of disrupted supply chains, food security, social vulnerability, forced migrations and intense emotional and mental trauma for the survivors,” he says.

Read more: A Perfect Storm: How the deadly 2022 Durban floods hold crucial lessons for the future of the city and others like it

“The hidden costs tend to compound rapidly in the absence of a coherent adaptation strategy,” he says. “These have profound and long-lasting effects on vulnerable communities that are repeatedly affected.”

The start is an accurate early warning ecosystem that KZN, surprisingly, is relatively well provided for. The South African Weather Service’s existing meteorological impact-based early warning system is complemented by uMngeni-uThukela Water’s flood forecasting early warning system based on hydrological monitoring (streamflow measurement) and hydraulic modelling.

However, the technology alone is far from perfect, as flood predictions’ accuracy and lead time hinge on several factors. Ineffective dissemination further undermines effective and early response capabilities, says Mabhaudhi.

“A longer lead time is more uncertain, and a shorter lead time is more accurate, but you have less time to prepare and respond, and this has implications on how communities trust and respond to early warnings,” Mabhaudhi says.

“Summer thunderstorms are especially difficult to predict, even in the short term, while rain accompanied by cold fronts can be predicted with great accuracy, up to two or three days in advance.”

While cut-off low weather systems typically result in heavy rainfall over KZN, and have accounted for most of the flood events, these systems increasingly can be predicted with greater accuracy, thanks to the advances in weather forecasting and AI, according to Mabhaudhi.

The rise of social media has greatly enhanced efforts to raise the flood alarm with communities in peri-urban and urban areas.

“A good example is the community-based early warning system for the Quarry Road West community living along the Palmiet River, a partnership between eThekwini Municipality, the University of KwaZulu-Natal and the community. This system ensures early warnings from the weather service are disseminated through the municipality and shared with community members through social media groups. This proved life-saving during the April 2022 floods,” he says.

“However, the real problem is an apparent lack of anticipation, preparedness and early action among municipalities to tackle infrastructural challenges, associated with climate change.”

Read more: Early warning systems on floods are not enough; climate crisis literacy saves lives – experts

Climate- and nature-sensitive urban planning and a commitment beyond lip service to maintaining infrastructure are non-negotiable, says Mabhaudhi.

A corollary is enforcing bylaws and building awareness to regulate the urbanisation of towns and cities, specifically to restrict the settlement of flood-prone areas and land use change, which increases impervious surfaces and runoff at the expense of the natural environment.

The bodies of two children were recovered on Cutting Beach, Merebank, in the South of Durban on Wednesday morning, 26 February 2025. At that stage authorities could not confirm whether it was related to the Umlazi River incident. (Photo: Lauren Hendricks)

A road tanker washed up on a Durban beach amid floods and heavy rain on 12 April 2022. (Photo: Gallo Images / Darren Stewart)

“Uninhabited land near a water course and wetlands is often seen as an opportunity to erect a dwelling which, unless checked, draws more settlers,” Mabhaudhi says.

“It needs a whole-of-government and whole-of-society approach to address interlinked socioeconomic vulnerabilities that drive people into informal settlements, exposing them to climate risks, while strengthening both built and ecological infrastructure to withstand and buffer floods.

“The Climate Change Act provides a framework to start collaborating and coordinating a unified response to climate change.”

“By working together, across government, academia, civil society and communities, is the only way to effectively create awareness and develop solutions in communities most affected by climate change.” DM

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